Method for assisting during felling of a tree, and system for assisting during felling of a tree

ABSTRACT

A method assists during felling of a tree. The method includes the steps of: providing a property of the tree and/or a property of an environment of the tree; obtaining felling information related to an ideal felling direction of the tree based on the provided property; and outputting the obtained felling information.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. § 119 from GermanPatent Application No. EP 17179673.3, filed Jul. 4, 2017, the entiredisclosure of which is herein expressly incorporated by reference.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a method for assisting during felling of atree, and to a system for assisting during felling of a tree.

A method for assisting during felling of a tree and a system forassisting during felling of a tree are known.

The invention is based on the problem of providing a method forassisting during felling of a tree and a system for assisting during thefelling of a tree, which method and system each improve safety duringfelling, make it easier to prevent undesired damage, in particular tothe tree, during felling and/or allow simple further processing of thetree.

The invention solves this problem by providing a method and system forassisting during felling of a tree in accordance with claimedembodiments of the invention. Advantageous developments and/orconfigurations of the invention are described and claimed herein.

The, in particular automatic, method according to the invention forassisting or supporting during felling of a tree comprises the steps: a)providing, in particular automatically providing, or obtaining aproperty of the tree and/or a property of an environment of the tree; b)obtaining, in particular automatically obtaining, felling informationrelated to an ideal felling direction of the tree based on the providedproperty; and c) outputting, in particular automatically outputting, theobtained felling information.

The method allows safety to be improved during felling, in particularfor a forestry worker executing the felling. In addition or as analternative, the method allows it to be made easier to prevent undesireddamage, in particular to the tree, during felling. Further in additionor as an alternative, the method allows simple further processing of thetree. Therefore, a maximum economic profit can be made from the tree.

A deviation from the ideal felling direction can lead to the treefalling and/or becoming trapped on something in an undesired manner.Furthermore, a deviation can lead to the tree, in particular its trunk,ripping and/or splitting. In addition, a deviation can lead to the treebeing in an unfavourable position. This may reduce an economic profitwhich can be made from the tree. By virtue of outputting the fellinginformation, a risk of these disadvantages occurring can be reduced oreven avoided.

In particular, the ideal felling direction can be obtained. The fellinginformation can be based on the obtained felling direction or can beobtained based on the obtained felling direction. The felling directioncan include or be a compass direction.

The tree can be standing, in particular living.

The property can include or be a value and/or an amount.

The step b) can be executed at the same time as step a) and/or after thesaid step a). The step c) can be executed at the same time as step b)and/or after the said step b).

In one development of the invention, the step a) includes: receiving, inparticular receiving in a cable-free or wire-free manner, or calling upthe property, in particular from a database and/or a network, inparticular from the Internet. In particular, the database can include aforestry file which can include the property.

In one configuration of the invention, the method comprises the step:obtaining, in particular specifying or identifying, a position and/or amarking of the tree. The step a) includes: receiving the property basedon or depending on the obtained position and/or the obtained marking. Inparticular, the property of the tree at this position and/or theproperty of the environment of this position can be received based onthe obtained position. The property of the tree with this marking and/orthe property of the environment of this tree can be received based onthe obtained marking. In addition or as an alternative, the position ofthe tree with this marking can be received based on the obtainedmarking. The property can be received based on the received position. Inparticular, the marking can be made on the tree, in particular by theforestry worker. The marking can include at least one symbol, inparticular a letter and/or a number, and/or a code, in particular a barcode and/or a QR code.

In one development of the invention, the step a) includes: identifyingthe property using optical identification, in particular in combinationwith photogrammetry, and/or inertial measurement and/or a spirit leveland/or a compass and/or local position determination and/or satelliteposition determination. In particular, the tree and/or the environmentof the tree can be described by position coordinates and/or orientationangles. The position coordinates and/or the orientation angles can beidentified by in each case at least one of the said techniques. Inparticular, optical identification can be performed from differentidentification positions and/or with depth information. In particular,the above-described marking can be obtained using opticalidentification. In particular, the above-described position can beobtained using the local position determination and/or the satelliteposition determination.

In one development of the invention, the property of the tree includes ageometry of the tree and/or a surface characteristic of the tree and/ora tree species of the tree or is a specific property of this kind of thetree. In addition or as an alternative, the property of the environmentof the tree includes at least one position of at least one adjacent treeand/or at least one position of at least one hazardous point and/or atleast one position of at least one logging trail and/or a shape and/or aslope of the environment and/or a wind direction and/or a wind speed oris a specific property of this kind of the environment. A fellingresponse of the tree can depend on or at least be influenced by thegeometry, the surface characteristic and/or the tree species of thetree. In particular, the geometry of the tree can include or be a heightand/or a diameter and/or a curvature and/or a slope and/or a contourand/or a shape and/or a branch distribution and/or a crown weight of thetree or its trunk. The geometry of the tree can be identified, inparticular, by in each case at least one of the above-describedtechniques for identifying the property. In particular, the tree speciesand/or a state of health of the tree can be identified, in particularobtained, from the surface characteristic. The surface characteristicand/or the state of health can include damage, in particular wooddamage. The state of health can include a pest infestation and/orrotting. The tree species can be oak or spruce or pine or beech oranother tree species. The surface characteristic and/or the tree speciescan be identified, in particular, by the above-described opticalidentification. In particular, a fibre orientation of the tree or of itstrunk can be identified, in particular obtained, from the geometryand/or the surface characteristic of the tree. The felling response ofthe tree can depend on or at least be influenced by the wind directionand/or the wind speed. A response of the tree during felling or afterfelling or further processing of the tree can depend on or at least beinfluenced by the position of the adjacent tree, the position of thehazardous point, the position of the logging trail, the shape of theenvironment and/or the slope of the environment. The logging trail canbe used to collect the felled tree. The shape of the environment can beflat or rugged. In particular, the environment can include rocks and/orcliffs. The slope of the environment can include a gradient and/or aninclined direction. The position of the adjacent tree, the position ofthe hazardous point, the position of the logging trail, the shape of theenvironment and/or the slope of the environment can be identified, inparticular, by in each case at least one of the above-describedtechniques for identifying the property. The wind direction and/or thewind speed can be received.

In one development of the invention, the step b) includes: obtaining afree felling area for the tree and/or a logging direction to a loggingtrail and/or a felling retreat for the forestry worker based on theprovided property. The felling information related to the ideal fellingdirection of the tree is obtained based on the obtained free area and/orthe obtained logging direction and/or the obtained felling retreat. Inother words: obtaining the felling direction of the tree in such a waythat the tree does not fall on an adjacent tree and/or a hazardous pointin the environment, in particular during felling, and/or that the treefalls in the direction of a logging trail and/or that the tree leavesfree at least one logging retreat during felling. The felling area canbe referred to as a felling corridor. The felling retreat can or shouldrun inclined through 45° in relation to the felling direction.

In one development of the invention, the felling information includes:the ideal felling direction of the tree and/or at least a part of anideal course of at least one cut to be executed in the tree for fellingthe tree in the ideal felling direction and/or at least one idealposition and/or at least one ideal orientation or alignment of a cuttingapparatus executing the cut. In particular, the felling information caninclude where and/or how execution of the cut can or should be startedand/or terminated on the tree. The ideal position can be a startingposition or an end position. The ideal orientation can be a startingorientation or an end orientation. In particular, the at least one partof the ideal course of the at least one cut to be executed can beobtained based on the ideal felling direction. The ideal position and/orthe ideal orientation can be obtained based on the at least one part ofthe ideal course. The part of the course can be, in particular, a start,in particular a starting line, or an end, in particular an end line, ofthe course. The at least one cut to be executed can be selected from agroup, the group comprising: a kerf lower cut, a kerf upper cut and afelling cut. In particular, the kerf lower cut, the kerf upper cut andthe felling cut in this order or the kerf upper cut, the kerf lower cutand the felling cut in this order can form a cutting sequence. The kerflower cut and the kerf upper cut can or should meet exactly at a kerfchord and neither of the two cuts should go beyond the other. The kerflower cut and the kerf upper cut can form a kerf or a felling wedge. Thekerf can determine a falling direction of the tree and can be used toenable tipping of the tree in the desired felling direction. Inaddition, the kerf upper cut or its course can or should be at least atan angle of 45° in relation to the kerf lower cut or its course in orderto create a sufficiently large opening in this way. In this way, it ispossible to ensure that, during felling, the tree cannot sit with thekerf roof on the kerf base and the trunk cannot rip along thelongitudinal axis in this sitting position. The felling cut can orshould be started or made one tenth of the diameter of the trunk, but atleast 3 centimetres (cm), laterally next to the kerf chord. Thishorizontal offset can be called the hinge width. Furthermore, thefelling cut can or should be started one tenth of the diameter of thetrunk, but at least 3 cm, above the kerf chord. This vertical offset canbe called the hinge step. An end line of the felling cut, which can becalled the hinge chord, can or should run parallel to the kerf chord.The hinge width and hinge step can form a hinge which can hold the treeduring felling work and safely guide the said tree during felling. Steepcutting of the hinge width and/or the hinge step can lead to a deviationfrom the intended felling direction. In addition, the fellinginformation can include apparatus information. The apparatus informationcan include: a power of a motor in the case of a motor-driven cuttingapparatus, a length of a blade of the cutting apparatus and/or whetherand which other auxiliary appliances, such as wedges or a felling lever,should be used for felling the tree.

In one refinement of the invention, the felling information is outputusing optics and/or acoustics and/or haptics. This can provide theforestry worker with a relatively good perception of the fellinginformation. In particular, the output by optics can include a display.The output by optics can include superimposition or projection of thefelling information into a field of view of the forestry worker, inparticular in front of the tree. The output by optics can includeprojection of the felling information onto the tree. The output byhaptics can include vibration.

In one development of the invention, the method comprises the steps: d)identifying, in particular automatically identifying, at least a part ofan, in particular actual, course of a cut in the tree for felling thetree during execution thereof and/or identifying a position and/or anorientation of a cutting apparatus executing the cut during executionthereof; e) comparing, in particular automatically comparing, theidentified part of the course to an obtained part of an ideal course ofa cut to be executed in the tree for felling the tree in the idealfelling direction and/or comparing the identified position and/or theidentified orientation of the cutting apparatus to an obtained idealposition and/or an obtained ideal orientation of the cutting apparatusfor executing the cut to be executed, in particular during step d); andf) obtaining, in particular automatically obtaining, and outputting, inparticular automatically outputting, cutting information for executingthe cut based on the comparison during step d). This can allow adeviation from the at least one part of the ideal course of the cut tobe executed to be avoided during execution of the cut or to return tothe ideal course in the event of a deviation. The cutting informationcan include an instruction to return, in particular a positioninstruction and/or an orientation instruction. In addition or as analternative, the cutting information can include an instruction toterminate the execution of the step. The cutting information can beoutput in the same way as the felling information. The part of thecourse of the cut and/or the position and/or the orientation of thecutting apparatus can be identified by the above-described techniquesfor identifying the property. The part of the course can be obtainedbased on the identified position and/or the identified orientation ofthe cutting apparatus.

The invention further relates to a system for assisting during fellingof the tree. The system can be configured, in particular, for executingthe above-described method. The system according to the invention has aprovision device, a determination device and an output device. Theprovision device is configured to provide the property of the treeand/or the property of the environment of the tree. The determinationdevice is configured to obtain the felling information related to theideal felling direction of the tree based on the provided property. Theoutput device is configured to output the obtained felling information.

The system can allow the same advantages as the above-described method.

In particular, the determination device can include or be a processor,in particular a CPU.

In one development of the invention, the provision device includes areceiver device configured to receive the property. The receiver unitcan include a mobile radio receiver unit, in particular a UMTS, WLANand/or Bluetooth receiver unit, or a receiver unit based on anothertechnology.

In one development of the invention, the provision device includes anidentification device configured to identify the property. Theidentification device includes a camera and/or an inertial measuringunit and/or the spirit level and/or the compass and/or a local positiondetermination device and/or a satellite position determination device.The camera can include a stereo camera and/or a TOF camera for depthinformation. TOF cameras are 3D camera systems which can measuredistances using the time of flight method. The inertial measuring unitcan include at least one acceleration sensor and/or at least one rate ofrotation sensor. The spirit level can be configured as an electrical ordigital spirit level. The compass can be configured as an electrical ordigital compass. The local position determination device canadvantageously be based on one or more different technologies, such asdistance measurements from node points, optical signals, radio waves,magnetic fields, acoustic signals, ultra-wideband, Bluetooth, WLAN,ultrasound and/or RFID. The satellite position determination device canbe configured for one or more satellite position determination systemssuch as NAVSTAR GPS, GLONASS, Galileo and/or BeiDou. In addition or asan alternative, the satellite position determination device can beconfigured as an RTK (real time kinematic) satellite positiondetermination device and/or as a differential satellite positiondetermination device.

In one development of the invention, the output device includes adisplay and/or a sound generator and/or a vibration device or is one ofthe above. In particular, the display can be configured to display thefelling information in the field of view of the forestry worker, inparticular in front of the tree, and/or to project or superimpose thesaid felling information into the said field of view, in particularbefore and/or during execution of the felling by the forestry worker.The display can be called a head-up display. This can be called virtualreality and/or augmented reality.

In one development of the invention, the system includes a protectivehelmet, a face shield and/or ear protection, safety goggles, aprotective glove, a smartwatch, an armband or a wristband or a bracelet,whereon the provision device and/or the output device are/is disposed.This allows the provision device and/or the output device to be worn onthe body of the forestry worker. Therefore, the forestry worker cancarry, in particular, the identification device, if present, with him.In other words, the identification device can identify what the forestryworker is currently working on. In particular, the display, if present,can be configured to display the felling information on or project thesaid felling information into a visor of the protective helmet, of theface shield and/or ear protection and/or of the safety goggles, ifpresent. The display can be called a head-mounted display.

In one development of the invention, the system includes the cuttingapparatus configured to execute the at least one cut in the tree forfelling the tree. In particular, the cutting apparatus can include or bea saw. The saw can include or be a motorized saw and/or a chainsaw. Inparticular, the cutting apparatus can be configured as a hand-heldcutting apparatus. Hand-held cutting apparatus can mean that the cuttingapparatus can have a maximum mass of 50 kilograms (kg), in particular of20 kg, in particular of 10 kg. The provision device and/or the outputdevice can be disposed on the cutting apparatus.

Other objects, advantages and novel features of the present inventionwill become apparent from the following detailed description of one ormore preferred embodiments when considered in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of an exemplary method according to the invention.

FIG. 2 is a perspective view of an exemplary system according to theinvention.

FIG. 3 is a further perspective view of the system of FIG. 2 whenproviding a property of a tree to be felled and a property of anenvironment of the tree.

FIG. 4 is a further perspective view of the system of FIG. 2 whenoutputting felling information.

FIG. 5 is a view of a longitudinal section of the tree of FIG. 3 duringfelling.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a method for assisting during felling of a, in particularstanding, tree 100 or its trunk 101, as can be seen in FIGS. 3 to 5. Themethod comprises the steps: a) providing a property EB of the tree 100and a property EU of an environment 101 of the tree 100; b) obtainingfelling information Info related to an ideal felling direction FR of thetree 100 based on the provided property EB, EU; and c) outputting theobtained felling information Info. In alternative exemplary embodiments,it may be sufficient when step a) can include the following: providingeither the property of the tree or the property of the environment ofthe tree.

FIGS. 2 to 5 show a system 10 for assisting during felling of the tree100. The system 10 is configured, in particular, for executing theabove-described method. The system 10 has a provision device 20, adetermination device 30 and an output device 40. The provision device 20is configured to provide the property EB of the tree 100 and theproperty EU of the environment 110 of the tree 100. The determinationdevice 30 is configured to obtain the felling information Info relatedto the ideal felling direction FR of the tree 100 based on the providedproperty EB, EU. The output device 40 is configured to output theobtained felling information Info. In alternative exemplary embodiments,it may be sufficient when the provision device can be configured toprovide either the property of the tree or the property of theenvironment of the tree.

Specifically, the provision device 20 includes an identification device22. The identification device 22 is configured to identify the propertyEB, EU. In the exemplary embodiment shown, the identification device 22includes a camera 23 and a satellite position determination device 28.In alternative exemplary embodiments, the identification device caninclude either the camera or the satellite position determinationdevice. In alternative exemplary embodiments, the identification devicecan further include, in addition or as an alternative, an inertialmeasuring unit, a spirit level, a compass and/or a local positiondetermination device.

Furthermore, the provision device 20 includes a receiver device 21. Thereceiver device 21 is configured to receive the property EB, EU. In theexemplary embodiment shown, the receiver device is configured as amobile radio antenna. In alternative exemplary embodiments, theprovision device can include either the identification device or thereceiver device.

In addition, the system 10 has a protective helmet 61, a face shieldand/or ear protection 62, a protective glove 64 and a smartwatch 65. Inthe exemplary embodiment shown, the camera 23, the satellite positiondetermination device 28 and the receiver device 21 are disposed, inparticular integrated, on the protective helmet 61, as can be seen inFIG. 2. In alternative exemplary embodiments, the provision device can,in addition or as an alternative, be disposed on the face shield and/orear protection, the protective glove and/or the smartwatch. Inalternative exemplary embodiments, the system can further include safetygoggles, an armband or a wristband or a bracelet, whereon the provisiondevice can be disposed.

In addition, the determination device 30 is disposed on the, or in the,protective helmet 61.

Accordingly, the step a) includes: identifying the property EB, EU usingoptical identification, in particular using the camera 23, and satelliteposition determination, in particular using the satellite positiondetermination device 28. In alternative exemplary embodiments, it may besufficient when step a) includes: identifying the property either usingoptical identification or using satellite position determination. Inalternative exemplary embodiments, the step a) can further include, inaddition or as an alternative: identifying the property using inertialmeasurement and/or a spirit level and/or a compass and/or local positiondetermination.

In addition, the step a) includes: receiving the property EB, EU, inparticular using the receiver device 21.

Specifically, the method includes the step: obtaining a position PO, inparticular using the satellite position determination device 28, and amarking KN of the tree 100, in particular using the camera 23. The stepa) includes: receiving the property EB, EU based on the obtainedposition PO and the obtained marking KN. In alternative exemplaryembodiments, the method can include the step: obtaining either theposition or the marking of the tree. Accordingly, the step a) caninclude: receiving the property based on either the obtained position orthe obtained marking.

In the exemplary embodiment shown, a forestry worker 90 wears theprotective helmet 61, as can be seen in FIG. 3. The forestry worker 90,in particular firstly, walks around the tree 100. In the process, theproperty EB of the tree 100 is optically identified from variousidentification positions using the camera 23.

Specifically, the property EB of the tree 100 includes a geometry GE ofthe tree 100 and a surface characteristic OE of the tree 100 and a treespecies BE of the tree 100. In alternative exemplary embodiments, it maybe sufficient when the property of the tree can include either thegeometry or the surface characteristic or the tree species. The state ofhealth of the tree 100 is identified, in particular obtained, from thesurface characteristic OE. Fibre orientation of the tree 100 or of itstrunk 101 is identified, in particular obtained, from the geometry GEand the surface characteristic OE of the tree.

In addition, the marking KN of the tree 100 is obtained using the camera23 while the said forestry worker is walking around. The property EU ofthe environment 110 of the tree 100 is received based on the obtainedmarking KN. In alternative exemplary embodiments, the property of thetree can, in addition or as an alternative, be received based on theobtained marking.

The position PO of the tree 100 is further additionally obtained usingthe satellite position determination device 28. The property of theenvironment 110 of the tree is received based on the obtained positionPO. In alternative exemplary embodiments, the property of the tree can,in addition or as an alternative, be received based on the obtainedposition.

Specifically, the, in particular received, property EU of the tree 100includes a wind direction and a wind speed WRG.

In addition, the forestry worker 90, in particular secondly, walksaround in the environment 110 of the tree. In the process, the propertyEU of the environment 110 is optically identified from variousidentification positions using the camera 23.

Specifically, the, in particular identified, property EU of theenvironment 110 includes at least one position PON of at least oneadjacent tree 111 and/or at least one position POG of at least onehazardous point 112 and/or at least one position POR of at least onelogging trail 113 and/or a shape and/or a slope FNU of the environment.

In alternative exemplary embodiments, it may be sufficient when theproperty of the environment can include either the at least one positionof at least one adjacent tree or the at least one position of at leastone hazardous point or the at least one position of at least one loggingtrail or the shape and/or the slope of the environment or the winddirection and/or the wind speed.

In the exemplary embodiment shown, there are three adjacent trees 111 inthe form of protected trees in the environment 110 of the tree 100, ascan be seen in FIGS. 3 and 4. Furthermore, there is a hazardous point112 in the form of a electricity pylon in the environment 110. Inaddition, there is a logging trail 113 in the environment 110, at thetop or in compass direction north in FIGS. 3 and 4. The shape FNU of theenvironment 110 is further flat, with the exception of a rock. Inaddition, the environment is sloping, to the top right or in compassdirection north-east, as indicated by dashed contour lines, in FIGS. 3and 4. Furthermore, there is a wind direction WRG, to the top right orin compass direction north-east in FIGS. 3 and 4.

The geometry GE, the surface characteristic OE and the tree species BEdo not give rise to any particular felling response of the tree 100.

However, the geometry GE of the tree 100 includes a height of the tree100 and a value of the height GE is relatively larger than a distancebetween the position PO of the tree 100 and the positions PON of theadjacent trees 111, a distance between the position PO and the positionPOG of the hazardous point 112 and a distance from the rock.Furthermore, one of the positions PON of one of the adjacent trees 111is between the position PO of the tree 100 and a next position POR ofthe logging trail 113.

Therefore, in the event of a non-ideal felling direction, in particularin the event of felling directly in the direction of the logging trail113, there is risk of the tree 100 falling onto one of the adjacenttrees 111, the hazardous point 112 or the rock. Furthermore, there is arisk of the wind changing or at least influencing a direction of thetree 100 during felling. On account of the gradient of the environment110, there is also a risk of the tree 100 or its trunk 101 rolling awayand/or slipping away in the case of an unfavourable position afterfelling, in particular after removal of its crown and/or of branches.

Therefore, a response of the tree 100 during felling and after fellingand further processing of the tree 100 depends on the positions PON ofthe adjacent trees 111, the position POG of the hazardous point 112, theposition POR of the logging trail 113, the shape and/or the slope FNU ofthe environment 110 and/or the wind direction and/or the wind speed WRG.

Specifically, the step b) includes: obtaining a free felling area 120for the tree 100 and a logging direction 121 to the logging trail 113and a felling retreat 122 for the forestry worker 90 based on theprovided property EB, EU. The felling information Info related to theideal felling direction FR of the tree 100 is obtained based on theobtained free area 120 and the obtained logging direction 121 and theobtained felling retreat 122. Specifically, two felling retreats 122 areobtained, which are each intended to run or run inclined through 45° inrelation to the felling direction FR. In alternative exemplaryembodiments, the step b) can include: either obtaining the free fellingarea or the logging direction or the logging retreat. Accordingly, thefelling information can be obtained based on either the obtained freearea or the obtained logging direction or the obtained felling retreat.

In the exemplary embodiment shown, the obtained ideal felling directionFR is to the top right or in compass direction north-east in FIGS. 3 and4. Therefore, the tree 100 can fall into a gap between two of theadjacent trees 111. In the process, the tree 100 can fall with the wind.After felling, the tree 100 can lie perpendicular to the gradient of theenvironment 110 and therefore securely. Furthermore, the ideal fellingdirection FR is at a relatively small angle in relation to the loggingdirection 121.

The output device for outputting the obtained felling informationincludes a display 41, a sound generator 42 and a vibration device 43.In alternative exemplary embodiments, it may be sufficient when theoutput device can include either the display or the sound generator orthe vibration device.

In the exemplary embodiment shown, the display 41 is disposed, inparticular integrated, on the protective helmet 61, as can be seen inFIG. 2. Specifically, the protective helmet 61 has a visor. The display41 is configured to display the felling information Info on the visor ofthe protective helmet 61 in a field of view of the forestry worker 90,in particular in front of the tree 100, and/or to project the saidfelling information into the field of view in front of the tree 100. Inalternative exemplary embodiments, the display can be disposedelsewhere.

Furthermore, in the exemplary embodiment shown, the sound generator 42is disposed, in particular integrated, on the face shield and/or earprotection 62. In alternative exemplary embodiments, the sound generatorcan be disposed elsewhere.

In the exemplary embodiment shown, the vibration device 43 is alsodisposed, in particular integrated, on a cutting apparatus 50. Inalternative exemplary embodiments, the vibration device can be disposedelsewhere.

Accordingly, the felling information Info is output using optics,acoustics and haptics in step c). In alternative exemplary embodiments,it can be sufficient when the felling information can be output usingeither optics or acoustics or haptics.

Specifically, the felling information Info includes: the ideal fellingdirection FR of the tree 100 and at least a part IST of an ideal courseISV of at least one cut AS to be executed in the tree 100 for fellingthe tree 100 in the ideal felling direction FR and at least one idealposition IPOS and at least one ideal orientation IORS of the cuttingapparatus 50 executing the cut AS, as can be seen in FIGS. 4 and 5. Theat least one part IST of the ideal course ISV of the at least one cut ASto be executed is obtained based on the ideal felling direction FR, inparticular using the determination device 30. The ideal position IPOSand the ideal orientation IORS are obtained based on the at least onepart IST of the ideal course ISV, in particular using the determinationdevice 30. In alternative exemplary embodiments, it may be sufficientwhen the felling information can include: either the ideal fellingdirection or the at least one part of the ideal course of the cut to beexecuted or the ideal position or the ideal orientation of the cuttingapparatus executing the cut.

In the exemplary embodiment shown, the felling information Infospecifically includes where and how execution of the cut AS on the tree100 or its trunk 101 should be started. In particular, the fellinginformation Info is displayed in the field of view of the forestryworker 90, in particular in front of the tree 100.

Specifically, a kerf lower cut FKOS, a kerf upper cut FKDS and a fellingcut FAS are to be executed, as can be seen in FIG. 5. The kerf lower cutFKOS and the kerf upper cut FKDS meet exactly at a kerf chord KFS andneither of the two cuts goes beyond the other. The kerf lower cut FKOSand the kerf upper cut FKDS form a kerf. The kerf determines the fallingdirection of the tree 100. The felling cut FAS has a horizontal offsetHV in relation to the kerf chord FKS. The horizontal offset HV can becalled the hinge width. Furthermore, the felling cut FAS has a verticaloffset VV in relation to the kerf chord FKS. The vertical offset VV canbe called the hinge step. Steep cutting of the hinge width and/or thehinge step can lead to a deviation from the ideal felling direction FR.

In the exemplary embodiment shown, the geometric property GEadditionally includes a diameter of the tree 100 or its trunk 101. Thekerf lower cut FKOS, the kerf upper cut FKDS and the felling cut FAS orthe courses are obtained based on the diameter GE of the tree 100.

Furthermore, the system 10 includes the cutting apparatus 50. Thecutting apparatus 50 is configured to execute the at least one cut AS inthe tree 100 for felling the tree 100. Specifically, the cutting device50 includes a saw, in particular a motor-driven chainsaw.

In addition, the system 10 has an inertial measuring unit 24, a spiritlevel 25, a compass 26 and a local position determination device 27. Inthe exemplary embodiment shown, the inertial measuring unit 24, thespirit level 25, the compass 26 and the local position determinationdevice 27 are disposed on the cutting apparatus 50 or in the cuttingapparatus 50, as can be seen in FIG. 2. In alternative exemplaryembodiments, the inertial measuring unit and/or the spirit level and/orthe compass and/or the local position determination device can, inaddition or as an alternative, be disposed on the protective helmet, theface shield and/or ear protection, the protective glove, the smartwatch,safety goggles, an armband or a wristband and/or a bracelet. A positionPOS and an orientation ORS of the cutting apparatus 50 can be identifiedusing the inertial measuring unit 24, the spirit level 25, the compass26 and the local position determination device 27. In alternativeexemplary embodiments, the system can include either the inertialmeasuring unit or the spirit level or the compass or the local positiondetermination device.

The method further comprises the steps: d) identifying at least a partTST of an, in particular actual, course TSV of a cut TS in the tree 100for felling the tree 100 during execution thereof and/or identifying theposition POS and/or the orientation ORS of the cutting apparatus 50executing the cut during execution thereof; e) comparing the identifiedpart TST of the course TSV to the obtained part IST of the ideal courseISV of the cut AS to be executed in the tree for felling the tree 100 inthe ideal felling direction FR and/or comparing the identified positionPOS and/or the identified orientation ORS of the cutting apparatus 50 tothe obtained ideal position IPOS and/or the obtained ideal orientationIORS of the cutting apparatus 50 for executing the cut AS to beexecuted; and f) obtaining and outputting cutting information Info′ forexecuting the cut AS based on the comparison during step d). In theexemplary embodiment shown in FIG. 5, the course TSV of the cut TS, inparticular of the kerf lower cut FKOS, deviates upwards from the idealcourse ISV of the cut AS to be executed. The cutting information Info′includes an instruction to return to the ideal course ISV. In this case,an instruction to return downwards. In particular, the cuttinginformation Info′ is projected into the field of view of the forestryworker 90, in particular by means of a downwardly pointing arrow. Byreturning to the ideal course ZSIV of the cut TS, FKOS it is possible toensure that the tree 100 cannot sit with the kerf roof on the kerf baseduring felling and as a result the trunk 101 cannot rip along thelongitudinal axis.

The part TST of the course TSV of the cut TS and/or the position POSand/or the orientation ORS of the cutting apparatus 50 can be identifiedby the above-described techniques for identifying the property EB, EU.The part TST of the course TSV can be obtained based on the identifiedposition PORS and/or the identified orientation ORS of the cuttingapparatus 50. A physical expansion or a physical extension of thecutting apparatus 50, in particular an expansion of a guide rail or achain bar of the saw 50, is taken into account during identification ofthe position POS and the orientation ORS of the cutting apparatus 50executing the cut TS using the inertial measuring unit 24, the spiritlevel 25, the compass 26 and the local position determination device 27.

As is made clear by the exemplary embodiments shown and explained above,the invention provides an advantageous method for assisting duringfelling of a tree and an advantageous system for assisting duringfelling of a tree, which method and system each improve safety duringfelling, make it easier to prevent undesired damage, in particular tothe tree, and allow simple further processing of the tree.

The foregoing disclosure has been set forth merely to illustrate theinvention and is not intended to be limiting. Since modifications of thedisclosed embodiments incorporating the spirit and substance of theinvention may occur to persons skilled in the art, the invention shouldbe construed to include everything within the scope of the appendedclaims and equivalents thereof.

What is claimed is:
 1. A method for assisting during felling of a tree,the method comprising the steps of: a) providing, using a provisiondevice, a property of the tree and/or a property of an environment ofthe tree; b) obtaining, using a determination device, fellinginformation related to an ideal felling direction of the tree based onthe provided property; c) outputting, using an output device, theobtained felling information; d) using the provision device, identifyingat least a part of a course of a cut in the tree for felling the treeduring execution thereof and/or identifying a position and/or anorientation of a cutting apparatus executing the cut during executionthereof, e) using the determination device, comparing the identifiedpart of the course to an obtained part of an ideal course of a cut to beexecuted in the tree for felling the tree in the ideal felling directionand/or comparing the identified position and/or the identifiedorientation of the cutting apparatus to an obtained ideal positionand/or an obtained ideal orientation of the cutting apparatus forexecuting the cut to be executed; and f) obtaining, using thedetermination device, and outputting, using the output device, cuttinginformation for executing the cut based on the comparison during stepd).
 2. The method according to claim 1, wherein the step a) includes:receiving the property.
 3. The method according to claim 2, furthercomprising the step of: obtaining a position and/or a marking of thetree, wherein the step a) includes: receiving the property based on theobtained position and/or the obtained marking.
 4. The method accordingto claim 1, wherein, the step a) includes: identifying the propertyusing optical identification, inertial measurement, a spirit level, acompass, local position determination, and/or satellite positiondetermination.
 5. The method according to claim 1, wherein the propertyof the tree is one or more of a geometry of the tree, a surfacecharacteristic of the tree or a tree species of the tree, and/or theproperty of the environment of the tree includes at least one positionof at least one adjacent tree, at least one position of at least onehazardous point, at least one position of at least one logging trail, ashape and/or a slope of the environment, a wind direction, and/or a windspeed.
 6. The method according to claim 1, wherein the step b) includes:obtaining a free felling area for the tree, a logging direction to alogging trail and/or a felling retreat for a forestry worker based onthe provided property, and the felling information related to the idealfelling direction of the tree is obtained based on the obtained freearea, the obtained logging direction and/or the obtained fellingretreat.
 7. The method according to claim 1, wherein the fellinginformation includes one or more of: the ideal felling direction of thetree, at least a part of an ideal course of at least one cut to beexecuted in the tree for felling the tree in the ideal fellingdirection, or at least one ideal position and/or at least one idealorientation of a cutting apparatus executing the cut.
 8. The methodaccording to claim 1, wherein in step c), the felling information isoutputted using optics, acoustics and/or haptics.